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            <span>封面词条：</span><a class="title" target="_blank" href="/wiki/detail/id/753">Linux信号机制与信号处理</a>
            <p class="desc">信号(signal)是Linux进程间通信的一种机制，全称为软中断信号，也被称为软中断。信号本质上是在软件层次上对硬件中断机制的一种模拟。与其他进程间通信方式（例如管道、共享内存等）相比，信号所能传递的信息比较粗糙，只是一个整数。但正是由于传递的信息量少，信号也便于管理和使用，可以用于系统管理相关的任务，例如通知进程终结、中止或者恢复等。每种信号用一个整型常量宏表示，以SIG开头，比如SIGCHL...</p>
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